IT was Christmas dinner in the Andrew Lloyd Webber household two years ago when one of the guests round the table was American director Joel Schumacher. The conversation moved to The Phantom Of The Opera, the Lloyd Webber musical that has been seen by an estimated audience of 80 million people and taken over $3.2 billion at the theatre box-office.

It wasn't the first time that the composer and the film-maker had talked about turning the stage show into a movie. Lloyd Webber approached Schumacher to direct a Phantom film after seeing his 1988 vampire thriller The Lost Boys.

"We were going to make it in 1990 with original stars Michael Crawford and Sarah Brightman, then for a whole list of professional and personal reasons Andrew had to abort the project," recalls Schumacher, director of Batman Forever, The Client, Falling Down and Phone Booth.

He was doing post-production on the real life Irish drama Veronica Guerin in London when The Phantom reared his ugly head again.

Both he and Lloyd Webber had firm ideas about how the successful musical, about the disfigured Phantom and his young operatic protg Christine, should be transferred to the big screen. "The first thing I said was that if you analyse the story Christine is very young and the story is the awakening of many things in her case.

"I said that I needed a young cast. If they were unknown, I wanted the freedom to cast whoever was right for the parts. And Andrew insisted that they do their own singing," says the director.

Musically, they worked differently that usual on films where performers mime to a pre-recorded soundtrack. "Instead, the singers did temporary tracks and had total freedom to act the music. They went back into the studio afterwards and could record the tracks to their performances," says Schumacher.

This was particularly helpful for Emmy Rossum, who plays Christine. Only 16 when cast, her voice was maturing as they filmed. She had never seen The Phantom on stage before auditioning - and still hasn't. "I think it was good because I came to the character totally fresh," says Rossum, who starred in the summer disaster movie The Day After Tomorrow.

"I did have classical training when I was singing at the Metropolitan Opera from when I was little. I never thought I would get this part because I was 16 when I auditioned and the character had a lot of emotional things that went with it that were a lot of responsibility."

The casting of The Phantom was equally surprising as Scottish actor Gerard Butler has had no formal singing training. His previous screen roles include the bloodsucking vampire in Dracula 2000, the title role in the TV miniseries Attila The Hun and a leading role in Lara Croft Tomb Raider: Cradle Of Life.

There was nothing to indicate he was a singing star but Schumacher says: "I thought he would be a great Phantom. I knew he was a very interesting young actor and we'd talked about the possibility of working together. He'd mentioned once that he'd been in a band.

"The deal I had with Andrew was that the three leads would ultimately sing for him and that would be the determining factor. He wouldn't force me to put anything in the movie I didn't want and he wouldn't put in anyone whose voice was not right for the movie."

Butler recalls a previous experience of performing to an audience - at school, when he was sent to the class above to sing Mull Of Kintyre. "I was terrified. All the guys were looking at me as if to say, 'I always knew you were a fag'.

To prepare for the Phantom, he took singing lessons on the sly and rehearsed with musical director Simon Lee. All the same, the final audition proved an ordeal.

"Suddenly I'm standing in front of Andrew Lloyd Webber, in his house," he recalls. "Simon was playing the piano, reminding me to breathe, and I thought, 'I'm about to sing Music Of The Night, one of his most famous songs of all time, for the composer'. My legs started shaking."

He was convinced he hadn't been any good, although Schumacher recalls that the composer "jumped up and shook Gerry's hand enthusiastically."

The role of Raoul, the wealthy patron who takes a fancy of Christine, went to American actor Patrick Wilson, Emmy Award-nominated for the mini-series Angels In America. What most people in this country don't know is his background in musical theatre, having starred in US productions of Oklahoma! and The Full Monty.

"I saw the show years ago, possibly three or four times. I saw it as a fan, I watched as a kind not as an actor seeing role," he says.

His toughest task wasn't the singing, but riding bareback. "That's the fun part of doing movies, being able to train for things you've always wanted to do. It's not about ego or the arrogance of doing my own stunts but in a musical you play every emotion to the hilt."

He too won the approval of Lloyd Webber, who described him as "annoyingly perfect in all categories".

For Butler, the hard part were the prosthetics used to transform his face into the disfigured Phantom. He tells of a piece of silk thread being used to put down his eye and then having prosthetics put on top. The first three times it took nine hours to put on and one-and-a-half hours to get off. "We finally got it down to five hours, but there was a six-day space I was in at five in the morning for make-up," he says.

Schumacher ribs him about the make-up. "To make it look like real damage, it was done in so many layers. What Gerry is telling you is it's very difficult to be a movie star," he says.

l The Phantom Of The Opera (12A) opens in cinemas tomorrow and is reviwed on Page 10

Published: ??/??/2004